共查询到20条相似文献，搜索用时 174 毫秒
1.
2.
3.
试验旨在探讨检测过程中各因素对畸形率检测结果准确性的影响。试验建立测量不确定度模型,通过检测种猪常温精液精子畸形率,针对主要影响种猪精子畸形率可靠性的因素进行分析,建立种猪精液品质检测结果可靠性评估的方法。结果显示,测量标准不确定度结果为0.84%,扩展不确定度结果为1.68%。研究表明,生物投影显微镜的分辨率对精子畸形率检测的准确度影响较小,配制吉姆萨染色液浓度不影响检测结果,操作人员的技术水平对不确定度分量的结果影响较大。 相似文献
4.
5.
6.
随着肥料质量检测工作的深入开展,比色方法在许多检测项目中得到了越来越多的应用,作者在多年从事肥料检测工作的基础上,介绍肥料化验检测中各种比色方法所使用仪器的特点,阐述了比色方法中标准曲线的配制和制作,分析比色方法中环境因素对检测结果的影响,为肥料的科学分析检测提供技术依据,并提出一些粗浅见解。 相似文献
7.
8.
乳清粉是婴幼儿配方乳粉行业的主要原料之一,对其进行抗生素检测是原料验收的重要参考指标。本研究针对8个批次乳清粉原料,采用4种不同的抗生素检测方法进行了抗生素检测,包括国标法1、国标法2、利普斯50抗生素检测试剂盒法、Charm MRL酶联免疫试剂盒法。不同方法的检测结果存在很大差异,其中国标法1和酶联免疫试剂盒法获得了相同的结果,8个样品均为抗生素阴性。而国标法2及依据此法开发的快速检测试剂盒利普斯50检测则分别显示全阳性和部分阳性的矛盾结果。从上述结果可见,依据国标法2通过嗜热芽孢杆菌检测乳清粉产品抗生素,其结果稳定性欠佳,影响其检测结果可靠性的因素还有待进一步研究。 相似文献
9.
10.
在培养基的研发及生产中,促细胞增殖的能力是鉴定培养基质量优劣的一项重要指标,其检测方法也是至关重要的。近年来,各研究院和生物实验室普遍采用快速细胞增殖检测的方法,如CCK-8染色法。本文通过一系列实验分析影响细胞增殖检测结果的因素,以及这些因素的影响范围,从而确定最佳的实验条件。 相似文献
11.
应用目标取样法和扫描取样法同时对5只圈养黑熊(Ursus thibetanus)的15种行为进行了观察和记录,并对两种方法所得结果进行比较和讨论,评估两种方法在动物行为学研究中的可靠性。结果表明:两种方法所得的行为实际频次间存在显著差异(χ2=4.388,P=0.036,df=1),相对频次间无显著差异(χ2=0.468,P=0.494,df=1);行为持续时间的长短是影响两种方法所得结果间差异的主要因素,其与相对偏差值(Rela-tive Deviation,RD)之间存在显著的负相关关系(实际频次:r=-0.900,P=0.000,df=13;相对频次:r=-0.898,P=0.000,df=13);两种方法所得行为发生频次间存在显著正相关关系(r=0.965,P=0.000,df=13);扫描取样法所得行为间的差异性分析结果中70.5%与目标取样法的分析结果一致,29.5%存在分歧,且在分歧组中,参与差异性分析的两种行为的持续时间之差极显著大于一致组(χ2=10.082,P=0.001,df=1)。 相似文献
12.
《The Journal of Applied Poultry Research》2008,17(2):237-242
Litter is a common source of infectious agents in poultry production environments. Typical sampling methods only examine bacteria on the surface; however, bacteria recovered with these methods may not be representative of the population in the litter. To test this hypothesis, both shallow (top 2 in.) and deep (bottom 2 in.) litter samples were taken and compared with a surface sampling method (i.e., surgical shoe covers). Escherichia coli isolates were recovered from all 3 sample types and examined using an automated ribotyping system to determine the genetic diversity of the isolates. Twenty-six unique E. coli strains were recovered from the 3 different sampling methods. There was no correlation among strains between visit age, house, flock, or farm and ribogroups. Based upon the patterns of E. coli recovery among the different sample types, our results suggest that surface sampling methods are equally capable of recovering common isolates from the litter. Surgical shoe covers were easy to use, provided the same core population of isolates, and were comparable to shallow litter in the number of strains recovered. 相似文献
13.
利用表型数据构建狗牙根初级核心种质 总被引：1，自引：0，他引：1
本研究以831份狗牙根种质资源为试材,根据15个数量和质量性状,研究了狗牙根初级核心种质构建的方法。从总体取样规模(5%,10%,15%,20%,25%和30%)、组内取样比例(简单比例、对数比例、平方根比例和多样性比例)和取样方法(随机取样和聚类取样)3个层次探讨构建狗牙根初级核心种质的最佳取样策略,共形成48种取样策略。应用均值差异百分率、方差差异百分率、极差符合率和变异系数变化率4个参数来检验各取样策略的优劣。比较初始种质和初级核心种质两者基于主成分的样品分布图及性状间的相关系数,对构建的初级核心种质进行确认。结果表明,25%是最适宜的总体取样比例;4种组内取样比例中平方根比例优于简单比例、对数比例和多样性比例;2种取样方法中,聚类取样明显优于随机取样。最终确定25%的总体取样规模下,组内采用平方根比例和聚类抽样方法是构建狗牙根初级核心种质的最佳取样策略。根据获得的最佳取样策略最终在表型水平建立了包含208份种质的狗牙根初级核心种质,该种质可以作为整体资源的代表性样本,在狗牙根种质资源的充分开发和利用中发挥重要作用。 相似文献
14.
《Strength and Conditioning Journal》2020,73(5):584-593
Geomorphic reclamation creates variable topography and surface architecture, including rolling hillslopes and drainages. In contrast, traditional methods of reclamation result in landscapes susceptible to erosion due to steep, linear gradients. Geomorphic approaches to surface mine reclamation are relatively new, and hypotheses suggest the use of geomorphic principles in reclamation will improve vegetation outcomes relative to traditional methods. Topographic variability created by geomorphic reclamation likely results in more environmental heterogeneity, which should correlate with greater plant diversity. We examined revegetation outcomes of traditional and geomorphic reclamation on two reclaimed surface mines in Wyoming using nadir image sampling. Functional group diversity and measures of cover were compared between reclamation methods and undisturbed rangeland. Geomorphic reclamation supported greater total richness and greater native functional group richness relative to traditional reclamation. Native species cover on geomorphic reclamation, particularly for native perennial grasses, was either similar to undisturbed rangeland or greater than undisturbed rangeland and traditional reclamation. Reclamation shrub cover differed significantly from undisturbed sites, but was greater in geomorphic treatments. Results of nadir image analysis are compared to line-point intercept data from the same locations and outcomes are discussed in light of different reclamation techniques and sampling methods. Significant differences in cover categories were observed between nadir image and line-point intercept methods, however both methods revealed similar patterns between study sites. 相似文献
15.
Steyn HC McCrindle CM Du Toit D 《Journal of the South African Veterinary Association》2010,81(3):160-165
Heartwater, a tick-borne disease caused by Ehrlichia ruminantium, is considered to be a significant cause of mortality amongst domestic and wild ruminants in South Africa. The main vector is Amblyomma hebraeum and although previous epidemiological studies have outlined endemic areas based on mortalities, these have been limited by diagnostic methods which relied mainly on positive brain smears. The indirect fluorescent antibody test (IFA) has a low specificity for heartwater organisms as it cross-reacts with some other species. Since the advent of biotechnology and genomics, molecular epidemiology has evolved using the methodology of traditional epidemiology coupled with the new molecular techniques. A new quantitative real-time polymerase chain reaction (qPCR) test has been developed for rapid and accurate diagnosis of heartwater in the live animal. This method can also be used to survey populations of A. hebraeum ticks for heartwater. Sampling whole blood and ticks for this qPCR differs from routine serum sampling, which is used for many serological tests. Veterinary field staff, particularly animal health technicians, are involved in surveillance and monitoring of controlled and other diseases of animals in South Africa. However, it was found that the sampling of whole blood was not done correctly, probably because it is a new sampling technique specific for new technology, where the heartwater organism is much more labile than the serum antibodies required for other tests. This qPCR technique is highly sensitive and can diagnose heartwater in the living animal within 2 hours, in time to treat it. Poor sampling techniques that decrease the sensitivity of the test will, however, result in a false negative diagnosis. This paper describes the development of a skills training programme for para-veterinary field staff, to facilitate research into the molecular epidemiology of heartwater in ruminants and eliminate any sampling bias due to collection errors. Humane handling techniques were also included in the training, in line with the current focus on improved livestock welfare. 相似文献
16.
本文应用3 种检验分布型的方法分别检验了宽须蚁蝗蝗蝻的分布型,结果表明:宽须蚁蝗蝗蝻在草地上的空间分布型呈现聚集分布,其聚集强度随种群密度的升高而增加。应用Iwao 模型中的参数估计了野外调查时的最适抽样数。 相似文献
17.
对畜禽存栏量的调查是农业统计调查的重要内容之一,其统计调查方法主要是抽样调查。本研究旨在通过实例抽样调查,拟出合适的抽样方法对全国的基础母牛存栏量进行调查估计。采用二阶PPS(sampling with probability proportional to size)抽样、分层等比例抽样、分层二阶典型抽样对内蒙古敖汉旗肉牛存栏量进行调查,比较3种方法的准确度。结果表明, 在此3种方法10%的样本量下进行比较时,3种抽样方法按相对误差大小顺序排列为:分层二阶典型抽样＜分层等比例抽样＜二阶PPS抽样,其相对误差分层二阶典型抽样比分层等比例抽样、二阶PPS抽样分别小60.38%、92.83%;置信区间按大小顺序排列为:分层二阶典型抽样＜分层等比例抽样＜二阶PPS抽样。总体而言,分层二阶典型抽样的准确度相对较高,相对误差最小,仅为0.0412。故在实际应用当中,分层二阶典型抽样目前较为适用。 相似文献
18.
Federico Morandi Serena Panarese Ranieri Verin Fabio Ostanello Cinzia Benazzi Giuseppe Sarli 《Acta veterinaria Scandinavica》2012,54(1):17
Superficial inguinal lymph nodes from 72 wild boars examined in a previous immunohistochemical (IHC) study on porcine circovirus type 2 (PCV2) were selected for a PCV2 polymerase chain reaction (PCR) analysis. Four of these lymph nodes were PCV2-IHC strongly positive with PMWS histological lesions (outcome 1), 6 weak to mild PCV2-IHC positive without PMWS histological lesions (outcome 2) and 62 PCV2-IHC negative. Considering IHC the gold standard for diagnosis, the aims of the study were to evaluate the suitability of the PCV2-DNA extraction from formalin-fixed and paraffin-embedded (FFPE) tissue and the sensitivity and specificity of PCR under two IHC interpretations criteria: (A) the sample was considered positive if the result was outcome 1; (B) the sample was considered positive if the result was outcome 1 or 2. Under (A) criteria, sensitivity and specificity of PCR were 100% and 89.7%, respectively; the Cohen''s Kappa coefficient was 0.49. Under (B) criteria, sensitivity and specificity of PCR were 80.0% and 95.2%, respectively; the Cohen''s Kappa coefficient was 0.72. The high Cohen''s Kappa coefficient under the (B) interpretative criteria indicates good agreement between the two methods. In conclusion, 1) DNA extracted from FFPE specimens of wild boar is suitable for PCR and further represents a screening test for PCV2/PCVD (PCV2 Diseases) investigations in wild boar as well; 2) routine histological sampling can also be useful for PCV2 virological studies in wild boar. 相似文献
19.
Pausenberger A Schuster K Erhard MH 《Tier?rztliche Praxis. Ausgabe G, Grosstiere/Nutztiere》2012,40(2):77-84
Objective of the study was to evaluate whether the Colostrum Quality Counter (CQC), a new test method for immunoglobulin G (IgG) levels in newborn piglets, is easy to handle and provides comparable results to established testing regimes. Material and methods: Blood samples from 219 piglets from four different farms were tested for their IgG-concentrations using three different ELISA tests. Furthermore, double samples from 30 piglets were taken from both the anterior vena cava and from the tail to determine whether the collection site affects the results. The three tests used were the Colostrum Quality Counter (CQC; FarmulaONE, NL-Best), the internal IgG-ELISA from our laboratory (MUC) and a commercially-available IgG-ELISA (NAT; NatuTec, Frankfurt/Main, Germany). Results: MUC and NAT showed a higher correlation to each other than to the CQC when referring to the individual results per single piglet. The results from the CQC were higher and the standard deviation was significantly greater. The sampling site had no significant effect on the IgG concentrations measured. Clinical relevance: The CQC is a straightforward and simple test, being very convenient for sampling a large number of piglets. CQC results were inhomogeneous with some unusually high IgG-concentrations. MUC and NAT provided comparable results to one another and the IgG-concentrations showed a good correlation. 相似文献
20.
为研究空间尺度对物种多样性的影响,以内蒙古典型草原为对象,采用样线调查法分析Shannon指数和Patrick 丰富度指数2种α多样性指数随取样尺度的变化特征,结合分形理论和方法,得出2种α多样性指数的分形维数D。结果表明:随着取样尺度的逐渐增加,Shannon指数呈先迅速增加后降低的规律,而Patrick 丰富度指数达到最大值后则保持不变;5 m2(1 m×5 m)是该区域α多样性研究的最佳尺度;在5 m范围内,2种α多样性指数与取样尺度在双对数坐标上均呈极显著线性相关(P<0.01),相关系数(R)都在0.99以上,5 m后未表现出明显的线性规律;D值表明该区域物种组成简单。因此,在植物群落多样性研究中,采用较小的单个或多个样方要格外谨慎,应根据研究目的和多样性指标反应的特征来综合考虑取样尺度。 相似文献